Why Have Thyroid Cancer Rates Tripled? (LiveScience)

Study suggests it's not just from increased detection

From 1975 to 2013, the rate of new thyroid cancer diagnoses rose threefold, and researchers are reconsidering previous explanations for the phenomenon, according to a report in LiveScience.

For a long time, it was thought that the prevalence of thyroid cancer wasn't changing, but rather that doctors were paying it more attention and diagnosing more of the tumors.

But in a study published Friday, researchers found evidence that the underlying incidence may in fact have been growing -- especially for an aggressive papillary type of tumor. And mortality from thyroid cancer has been rising as well.

The researchers offered several explanations, including the possibility that declines in cigarette smoking may play a role.